Non-Contact Ir Temperature Measurements; Distance To Spot Ratio - Extech Instruments EX623A User Manual

5
Operation

5.17 Non-Contact IR Temperature Measurements

Do not directly view or point the laser at an eye. Low power visible lasers do not normally
present a hazard, but may present some potential for hazard if viewed directly for extended
periods of time.
Figure 5.12 IR Temperature measurements. Press the IRT button to activate the thermome-
ter and laser pointer. Release the button to switch off.
1. Rotate the function switch to the IRT position.
2. Press and hold the IRT button and aim the laser pointer toward the surface
to be measured.
3. With the IRT button still depressed, long press the MODE button to toggle
°F and °C temperature units.
4. Read the temperature measurement in the display.
5. The area of the surface to be measured must be larger than the measure-
ment spot size (to avoid measuring surrounding surfaces). The measure-
ment spot size depends on the distance the meter is from the target. See
the Distance to Spot ratio section, next, for more information.

5.17.1 Distance to Spot Ratio

The meter has an 8:1 distance to spot ratio. For example, at a distance of 8 in.
from the spot, the spot size is 1 in. The size of the measurement spot changes
as the meter's distance from the spot changes, as shown in Figure 5.13,
below.
#NAS100174; r. AA/97578/97616; en-US
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